Adjustable external vent valve



Nov. 12, 1963 F J. MARSEE ADJUSTABLE EXTERNAL VENT VALVE Filed Feb. 27,1961 FIG.2.

INV EN TOR.

FREDERICK J. MARSEE ATTORN Y5 United States Patent 3,110,745! ADJUSTABLE EXTERNAL VENT VALVE Frederick J. Marsee, Hazel Park, Mieln,assiguor to Holley Carburetor Qompany, Warren, Mich, a corporation ofMichigan Filed Feb. 27, 1961, Ser. N 91,755 Claims. (Cl. 261--3-t) Theinvention relates to valves and refers more particularly to an improvedadjustable external valve assembly for venting carburetor fuel bowls toatmosphere during idle operation of an associated internal combustionenglue or similar device.

In the operation of carburetors it is necessary to provide vents for thefuel bowl thereof due to fuel vapors produced therein. This isparticularly true during idle operation of the engine associated withthe carburetor after running of the engine and consequent heating of thecarburetor fuel bowl.

Means venting carburetor fuel bowls during idle operation of the engineassociated therewith have been provided in the past. Many of the ventingmeans of the past have comprised valves actuated by internal carburetorcomponents. Somevent valves of the past have been operated by thecarburetor accelerating pump cocking mechanism which is a desirablefeature since the accelerating pump cocking mechanism is normally in alimiting position during idle operation of the engine. Prior vent valvesoperated by the accelerating pump cocking mechanism of carburetors havehowever had the disadvantage that the accelerating pump displacementcould not be adjusted without eifecting the time of vent valveoperation.

It is therefore one of the objects of the present invention to provide avent valve assembly for use with a carburetor or similar device which isadjustable to vary the time of opening and closing thereof relative tocarburetor operating conditions.

Another object is to provide a carburetor fuel bowl vent valve assemblyactuated by the carburetor accelerator pump cocking mechanism which vent"alve assembly is adjustable to provide the same relative time ofoperation thereof regardless of the adjustment of the carburetoraccelerating pump displacement.

Another object is to provide a carburetor fuel bowl vent valve as setforth above which is external of the carburetor.

Another object is to provide a carburetor fuel bowl vent valve assemblycomprising a nut threaded into an upper portion of the carburetor fuelbowl, said nut including a passage extending therethrough for ventingthe fuel bowl and also including an annular groove therearound, a valvemember including a bifurcated end slidably engaged in the annular grooveand a valve end, the valve member being U-shaped to position the valveend over the bifurcated end in closing relation to the passage throughthe nut with the bifurcated end engaged in the annular groove, and astationary pin extending through the valve member operable to preventrotation of the valve member with the threaded nut.

Another object is to provide a carburetor including an accelerating pumpand accelerating pump cocking mechanism having an actuating arm in alimiting position during idle operation of the engine and a vent valveassembly adapted to be actuated by the actuating arm of the acceleratingpump comprising a threaded nut in the top of the carburetor fuel bowland having a passage extending therethrough for venting the fuel bowl,said threaded nut having an annular groove therearound exterior of thecarburetor fuel bowl, a valve member being U-shaped and having spacedapart bifurcated and valve ends, said valve member being positioned onsaid threaded nut with the Patented Nov. 12, 19%3 bifurcated endslidably engaged in the annular groove and the valve end positioned toclose said passage, and a pin extending through the arms of the U-shapedvalve member and into the carburetor fuel bowl top to prevent rotationof the valve member with the threaded nut, the valve member thus beingadjustable with respect to the carburetor fuel bowl from the exterior ofthe carburetor to position the valve end of the valve member in contactwith the actuating arm of the accelerating pump cocking mechanism in apredetermined position thereof before the limiting position thereof isreached regardless of adjustment of the cooking mechanism whereby thevalve is held opened by the accelerator pump cocking mechanism actuatingarm during idle operation of the engine to which the carburetor isattached.

Another object is to provide an adjustable vent valve which is simple inconstruction, economical to manufacture and efficient in operation.

Other objects and features of the invention will become apparent as thedescription proceeds, especially when taken in conjunction with theaccompanying drawings, illustrating a preferred embodiment of theinvention, where- FIGURE 1 is an elevation view of a carburetor partlyin section along the line 1-1 in FIGURE 2 illustrating an adjustablecarburetor fuel bowl vent valve assembly in accordance with theinvention.

FIGURE 2 is a top view of the carburetor vent valve assembly illustratedin FKGURE 1 taken in the direction of arrow 2 in FIGURE 1.

FIGURE 3 is a perspective view of the vent valve member of thecarburetor vent valve assembly illustrated in FIGURES 1 and 2.

With particular reference to the figures of the drawing, one embodimentof the present invention will now be disclosed.

In accordance with the invention the carburetor 10 mounted on the engine12 includes an accelerating pump 14 and the external carburetor fuelbowl vent valve assembly 16. In operation the valve member 13 of thevent valve assembly 16 is opened on engagement therewith of the end 263of the actuating arm 22 of the accelerating pump cocking mechanism 24and is adjustable relative thereto. f

More specifically the carburetor 10 includes the usual throttle valve 26and actuating lever 28 therefor mounted on the throttle valve shaft 39for rotation therewith on axial movement of link 32. The carburetor ltlfurther includes the carburetor fuel bowl 34 for storing fuel pumped tothe carburetor from fuel storage apparatus (not shown) for storagebefore being metered to the engine 12 by the carburetor it).

The accelerating pump 14 includes the cylinder 36 positioned within thefuel bowl 34- and the piston 38 reciprocal within the cylinder 36. Acheck valve 40 is provided in the bottom of the cylinder 36 whereby fuelfrom the carburetor fuel bowl 3 2- is drawn into the cylinder 36 on anupward stroke of the piston 38.

Piston 38 is drawn upward in opposition to the bias of the spring 42 bymeans of the actuating arm 22 of the accelerating pump cocking mechanism24 on clockwise movement thereof. Piston 38 is forced downwardly inFIGURE 1 by the spring 42 on counterclockwise pivoting of the actuatingarm 22 about pivot shaft 44 to force fuel within the cylinder 35 throughthe passage 46 and into the air intake of the carburetor to provideadded fuel for acceleration.

The accelerating pump cocking mechanism 24 includes the lever 43 securedto the shaft 30 for rotation therewith, the connecting links 5i) and 52and the actuating arm 22. Connecting link 52 and actuating arm 22 arerigidly secured to the pivot shaft 44 for rotation therewith. Cond ll'ld 35 necting link is pivotally secured at opposite ends to the leverand connecting link 52.

In operation, on pivoting of the throttle valve shaft 36 in a directionto cause opening of the throttle valve 26 the connecting link 5t? ismoved in a generally upward direction, as shown in FIGURE 1, to pivotthe connecting link 52 and actuating arm 22 in a counterclockwisedirection to provide a pumping stroke of the accelerating pump 14. Onsubsequent closing of throttle the accelerator pump cocking mechanism 24will return the piston 3% to the position illustrated in FIGURE 1 inpreparation for a subsequent pumping stroke of the piston 31%.

The vent valve assembly 16 comprises the threaded nut 54 having thepassage 56 therethrough and mounted on the carburetor so that thepassage 56 communicates with and vents the carburetor fuel bowl 34. Thenut 54 includes an annular groove 58 therein around the end thereofexterior of the carburetor fuel bowl. The carburetor vent valve assembly16 further includes the valve member 18 and the pin as.

The valve member is generally U-shaped and is best shown in FlGURE 3.Such valve member includes a bifurcated end 64 and a valve end as heldin spaced relation to each other by means of an open return bent portiones. Aligned openings 70 are provided through the arms of the U-shapedvalve member 13 adjacent the open return bent portion 69$ for thereception of pin in assembly, as shown in FIGURE 1, the bifurcated end64 of the valve member 18 is slidably received in the groove 5? of thenut 5 whereby the valve end as of the valve member 18 is resilientlyengaged with the outer end of the nut 54 to seal the vent passage 56from the carburetor fuel bowl 34 The pin 62 is held in a secure positionin the recess 74 in the carburetor 19 to prevent rotation of the valvemember it with the nut 54.

Thus in operation the valve member 18 may be positioned vertically asshown in FIGURE 1 by rotation of the nut 54. In such vertical movementthe valve memher 1% slides vertically on the pin 62 while the nut 54rotates with respect thereto and transfers the vertical movement of theend 72 thereof to the valve member 13 through the bifurcated end 64thereof held within the groove 58 in the nut 54'.

In over-all operation of the carburetor, when it is desired te changethe pumping stroke of the acclerating pump 14-, this is accomplished bymeans of adjustment of the accelerating pump cocking mechanism 24 tovary the limiting position of the actuating arm 22 when the throttlevalve 26 is in an idle position. The valve member 13 may then be easilyadjusted to contact the engaging end 2% or" the actuating arm 22 withthe actuating arm 22 in the same relation to the limiting positionthereof as before the adjustment of the actuating arm so that the valveend 66 of the valve member 18 is opened by actuating arm 22 only at therequired time to provide venting of the carburetor fuel bowl 3 3 throughpassage 56 during idle operation.

Thus it will be seen that in accordance with the invention a simplecarburetor fuel bowl vent valve assembly is provided which is operatedby the accelerating pump cocking mechanism 24 to open during idleoperation of the carburetor 1t) and which may be adjusted externally ofthe carburetor on adjustment of the accelerating pump stroke to insureventing of the carburetor fuel bowl only during idle operation.

The drawings and the foregoing specification constitute a description ofthe improved externally adjustable vent valve in such full, clear,concise and exact terms as to enable any person skilled in the art topractice the invention, the scope of which is indicated by the appendedclaims.

What I claim as my invention is:

1. A carburetor having a fuel bowl, a vent valve for said fuel bowl,adjustable means Within said carburetor the for opening said vent valvein accordance with the position of the adjustable means, said vent valveincluding an annular externally threaded nut threaded .in an opening inthe carburetor fuel bowl for adjustment in directions into and out ofthe carburetor fuel bowl, said vent valve extending over the outer endof the nut and operable in one position to prevent venting of the fuelbowl through the nut, means for preventing rotation of the vent valvewith the nut, and means for adjusting the nut and vent valve relative tothe fuel bowl.

2. A carburetor having a fuel bowl, a vent valve assembly for said fuelbowl including a nut threaded in an opening in the fuel bowl and havinga passage therethrough, said nut being rotatable for adjustment into andout of the fuel bowl, and a valve member having an arm portion within aperipheral groove in said nut whereby the valve member is movableaxially with said nut, said valve member having another arm portionextending over the passage in said nut and operable as a valve in oneposition to close said passage and prevent venting of the fuel bowlthrough said nut, adjustable means within said fuel bowl for opening thevalve in accordance with the position of the nut and valve member, andmeans for preventing rotation of the valve member with the nut.

3. An adjustable valve assembly for venting a carburetor fuel bowl,comprising a rotatable annular member of axial extent adjustablevertically in an opening in said fuel bowl and provided exteriorly ofsaid fuel bowl with a peripheral grooe, a valve member having an arm insaid peripheral groove and having an arm extending over the outer end ofsaid annular member and operable as a valve in one position to closesaid passage and prevent venting of the fuel bowl through said annularmember, and a vertical pin extending through both of said arms andsecured to said fuel bowl to prevent rotation of the valve member withthe annular member, the valve member being slidable vertically on saidpin upon rotation of said annular member relative to said fuel bowl.

4. An adjustable valve assembly for use in venting carburetor fuel bowlsand like structures comprising a hollow cylindrical valve adjustingmember secured in an opening in the structure to be vented for axialmovement into and out of the structure to be vented, a valve extendingover one end of the valve adjusting member, means operably associatedwith the valve and the structure to be vented for engaging the valve inone position thereof to open the valve and provide a vent passagethrough the valve adjusting member, and means for preventing rotation ofthe valve with the valve adjusting member while allowing movement of thevalve axially of the valve adjusting member with the valve adjustingmember on movement of the valve adjusting member into and out of thestructure to be vented.

5. Structure as set forth in claim 4 wherein the valve adjusting membercomprises an externally threaded nut rotatably secured in a threadedopening in the structure to be vented.

6. Structure as set forth in claim 4 wherein the valve includes asubstantially flat flexible portion extending over said one end of thevalve adjusting member and cantilevered at one side thereof for pivotalmovement to- Ward and away from the one end of the valve adjustingmember to open and close the passage therethrough.

7. Structure as set forth in claim 4 wherein the valve adjusting memberincludes an annular groove tllerearound adjacent said one end thereofand the valve comprises an open return bent U-shaped member havin g asubstantially fiat end extending over one end of the valve adjustingmember and a bifurcated end positioned within the annular groove in thevalve adjusting member.

8. Structure as set forth in claim 4 wherein the valve is an open returnbent U-shaped member and the means for preventing rotation of the valvewith the valve adjusting member comprises aligned openings extendingthrough the valve and a pin extending through said openings and securedto the structure to be vented.

9. An adjustable valve assembly for use in venting carburetor fuel bowlsand like structures comprising an externaily threaded nut having anmial-ly extending vent passage therethrough and an external annulargroove therearound threadedly received in an opening in the structure"to be vented for axial movement into and out of the opening, an openreturn bent flexible valve having one substantially flat end positionedover the outer end of the nut and one bifurcated end positioned withinthe annular groove around the nut and including a central portion havinga pair of aligned openings therethrough, and a pin extending through thealigned openings secured to the structure to be vented for preventingrotation of the valve with the nut while' permitting movement of thevalve axially with the nut on axial movement of the nut.

10. A carburetor having a fuel bowl and an accelerating pump includingan actuating arm therefor and a vent valve for said fuel bowl comprisingan externally threaded nut positioned within a threaded opening in thecarburetor fuel bowl adjacent the accelerating pump actuating arm foraxial movement into and out of the carburetor fuel bowl and having anannular groove around the outer end thereof, an open return bentflexible valve having a substantially fiat end extending over the outerend of the nut, a bifurcated end positioned within the annular groove inthe nut and a folded central portion having aligned openingstherethrough and a pin extending through the aligned openings andsecured to the carburetor adjacent the nut for preventing rotation ofthe valve with the nut While allowing axial movement of the valve withthe nut, said accelerating pump actuating arm engaging the end of thevalve extending over the outer end of the nut in one position thereof toprovide an external vent for the carburetor fuel bowl.

References Cited in the file of this patent UNITED STATES PATENTS151,548 Schmitz June 2, 1874 681,382 Westman Aug. 27, 1901 1,964,172Prentiss June 26, 1934 1,985,425 Prentiss Dec. 25, 1934 2,778,377Manchester Jan. 22, 1957 2,894,734 Wentwonth July 14, 1959 2,919,908Newman Ian. 5, 1960

10. A CARBURETOR HAVING A FUEL BOWL AND AN ACCELERATING PUMP INCLUDINGAN ACTUATING ARM THEREFOR AND A VENT VALVE FOR SAID FUEL BOWL COMPRISINGAN EXTERNALLY THREADED NUT POSITIONED WITHIN A THREADED OPENING IN THECARBURETOR FUEL BOWL ADJACENT THE ACCELERATING PUMP ACTUATING ARM FORAXIAL MOVEMENT INTO AND OUT OF THE CARBURETOR FUEL BOWL AND HAVING ANANNULAR GROOVE AROUND THE OUTER END THEREOF, AN OPEN RETURN BENTFLEXIBLE VALVE HAVING A SUBSTNANTIALLY FLAT END EXTENDING OVER THE OUTEREND OF THE NUT, A BIFURCATED END POSITIONED WITHIN THE ANNULAR GROOVE INTHE NUT AND A FOLDED CENTRAL PORTION HAVING ALIGNED OPENINGSTHERETHROUGH AND A PIN EXTENDING THROUGH THE ALIGNED OPENINGS ANDSECURED TO THE CARBURETOR ADJACENT THE NUT FOR PREVENTING ROTATION OFTHE VALVE WITH THE NUT WHILE ALLOWING AXIAL MOVEMENT OF THE VALVE WITHTHE NUT, SAID ACCELERATING PUMP ACTUATING ARM ENGAGING THE END OF THEVALVE EXTENDING OVER THE OUTER END OF THE NUT IN ONE POSITION THEREOF TOPROVIDE AN EXTERNAL VENT FOR THE CARBURETOR FUEL BOWL.